Answer
a)yes b)no c)no d)yes
Work Step by Step
a) $\frac{5+2}{5-4}=\frac{7}{1}=7\geq3$, thus yes
b) $\frac{4+2}{4-4}=\frac{6}{0}$, this is undefined, thus it cannot be a solution
c) $\frac{-4.5+2}{-4.5-4}=\frac{-2.5}{-8.5}\approx0.29\lt3$, thus no
d) $\frac{4.5+2}{4.5-4}=\frac{6.5}{0.5}=13\geq3$, thus yes
